Pneumatic transmission systems currently in use include a customer terminal, a teller terminal, a length of pneumatic transmission tube interconnecting the customer and teller terminals, and one or more blowers adapted to either supply a charge of air to or draw a vacuum from the pneumatic transmission tube. Often the pneumatic transmission system will incorporate some type of sophisticated carrier sensing device, which carrier sensing device tends to increase the complexity of the pneumatic transmission system, as well as the cost associated therewith. The sensing device is normally utilized incorporated into the pneumatic transmission system in order to monitor the position of the carrier and hence the need to energize the blowers associated with travel of the carrier through the transmission system.
One such pneumatic transmission system incorporating a complex and sophisticated carrier sensing device is disclosed in U.S. Pat. No. 4,971,481 to Foreman. Foreman discloses a terminal 10 having sensing means which comprise a piston 30 and air cylinder 36 which is operable to sense a pressure change in the shut off aperture 20 caused by movement of the carrier 22 past the shut off aperture and which activates a switch means 46 to terminate the stream of air from the pneumatic source 11a or 11b. The patent further discloses the use of the pressure monitor in conjunction with a catch for catching a carrier after it impacts on a stop and settles down on the catch.
A criticism of such complex carrier sensing devices is their relative complexity, which increases the overall cost of the pneumatic transmission system, and the detrimental effect on the overall reliability of the transmission system due to the reliability of the sensor device.
Another characteristic which is common amongst current pneumatic transmission systems is the custom nature of each teller terminal and customer terminal within a transmission system. More specifically, in current pneumatic transmission systems the customer terminal is of a custom construction having features and structure designed solely for the customer location. Similarly, the teller terminal will have features and structure specifically adapted for the teller location of the system. It will be appreciated that such custom construction of terminals for each location, namely customer and teller, greatly increases the costs associated with manufacturing a pneumatic transmission system, and additionally tends to decrease the reliability of same.
One such pneumatic transmission system which incorporates customized customer and teller terminals for use in commercial transactions is disclosed in U.S. Pat. No. 4,715,750 to Podoll et al. Podoll discloses a teller terminal T and a customer terminal C which include, respectively, relatively complex slide drawer mechanisms and pivoting drawer mechanisms.
It has therefore been an objective of the present invention to provide a relatively simple and inexpensive pneumatic transmission system which does not incorporate any of the aforementioned complex and expensive carrier sensor devices.
It has been another objective of the present invention to provide a simple and inexpensive universal terminal for a pneumatic transmission system, which terminal can be interchangeably used at either the customer terminal side or the teller terminal side of the system.